Explosive pest-scaring device



' Oct. 2, 1962 P. J. BENDER 3,056,376

EXPLOSIVE PEST-SCARING DEVICE 5 Sheets-Sheet 1 Filed Jan. 6, 1961INVENTOR Peim'JBmzdm Oct. 2, 1962 P. J. BENDER 3,056,376

EXPLOSIVE PEST-SCARING DEVICE Filed Jan. 6, 1961 5 Sheets-Sheet 2 we oINVENTOR Oct- 2, 1962 P. J. BENDER 3,056,376

EXPLOSIVE PEST-SCARING DEVICE Filed Jan. 6, 1961 5 Sheets-Sheet 3INVENTOR Pete/1 15mm Oct. 2, 162 P. J. BENDER 3,056,376

EXPLOSIVE PEST-SCARING DEVICE Filed Jan. 6, 1961 5 Sheets-Sheet 4INVENTOR PGWJ: Be/nde/r Oct. 2, 1962 P. J. BENDER 3,056,376

EXPLOSIVE PEST-SCARING DEVICE Filed Jan. 6, 1961 5 Sheets-Sheet 5 INV ENTOR PeZcWJBenuZeW ATTORNEYS 3,956,376 EXPLGSEVE EST-@CARiNG DEVICE PeterJ. Bender, River Road, RD. 2, New Castie, Del. Filed llan. 6, 1961, Ser.No. 81,044 6 Claims. (Cl. 116-23) This invention relates to an explosivedevice for scaring pests such as birds away from farm crops, and it moreparticularly relates to such a device which incorporates a carbide gun.

Explosion-generating means of the carbide gun type are now widely usedfor scaring birds such as black birds, crows and starlings away fromfarm crops. A rudimentary gun of this type is described in US. LettersPatent 1,384,366. However, presently existing guns now incorporateautomatic means for controlling the generation of the acetylene gas andfor firing it at periodic intervals thereby making them substantiallyautomatic in operation over an extended period of time, such as sixhours after they are charged with calcium carbide .and water. Most ofthe guns now being used in the United States are apparently beingimported from The Netherlands. These guns .are quite effective formaintaining an area of approximately two hundred yards directly in frontof them clear of birds and other animal pests; however, birds soonbecome accustomed to the sound and tempo of their regular firing andapproach much closer to the sides and rear of such guns.

An object of this invention is to provide a means for improving thepest-scaring ability of an automatic explosive device such as a carbidegun.

Another object is to accomplish such improvement by automaticallyvarying the direction of successive discharges of the gun; and

A further object is to also promote the transmission of the sound of theexplosions to longer distances.

In accordance with this invention, the explosive device is mountedeccentrically upon a turntable to cause its expanding gases to bedischarged substantially tangentially relative to the axis of theturntable. The resistance to motion of the turntable is set to cause theangle of orientation of the gun to vary after each explosion. Thiscauses the direction of transmission of the sound to progress about theaxis of the turntable which deters pests from encroaching to the rear ofthe gun. Furthermore, when the angle of movement of the gun varies inunequal increments such as approximately a little more than revolutionfor each explosion, the character of the sound resulting in a particulararea from the explosions changes appreciably each time the gun fireswhich prevents birds and animals from becoming accustomed to its patternand encroaching close to it.

The efficiency of such .a device can be further enhanced by choking anddiverting the expanding gases discharged from the gun. The chokingprovides the dual benefits of increasing the velocity of the dischargedgases and lengthening the transmission of the sound of their explosion.This promotes rotation of the turntable and also makes the gun eifectiveto longer distances. A particularly effective means of choking anddiverting may be provided by installing an elbow with a choked outletupon the end of the discharge tube of the gun with this outlet disposedtangentially to the axis of the turntable. This lengthens the tangentialradius of the expanding gases and also lengthens the range of theirsound. With such an elbow the axis of the gun itself may also bearranged tangentially to the axis of the turntable to add its reactionto the gases to that of those passing through the elbow in propellingthe turntable in its rotational movement.

Novel features and advantages of the present invention will becomeapparent to one skilled in the art from a reading of the followingdescription in conjunction with the accompanying drawings whereinsimilar reference characters refer to similar parts and in which:

FIG. 1 is a plan view of one embodiment of this invention;

FIG. 2 is a side view in elevation with the timing valve and gasgenerator sections partially broken away in cross section of theembodiment shown in FIG. 1;

FIG. 3 is an enlarged rear view in elevation with the timing valvesection partially broken away in cross section of the embodiment shownin FIG. 1 in one phase of operation;

PEG. 4 is an enlarged rear View in elevation with the timing valvesection partially broken away in cross section of the embodiment of thisinvention shown in FIG. 1 in another phase of operation; and

FIG. 5 is a plan view on a reduced scale of the embodiment shown in FIG.1 in various successive angular orientations.

In FIG. 5 is shown a pest-scaring device it) including an automaticexplosion-generating means on gun 12 mounted upon a movable section 14of turntable 16. Explosion-generating means 12 is mounted eccentricallyto the axis of rotation 18 of turntable 16 for discharging the expandinggases 2% tangentially relative to axis 18. These expanding gases 2%cause a reverse reaction upon explosion-generator 12 and the movableportion 14 of turntable 16 upon which it is mounted. This reaction istangential to axis 18 and propels movable portion 14 and gun 12 in arotational movement about .axis 18 which causes each explosion to varythe angular orientation of gun 12. The resistance of turntable 16 tothis rotation is, for example, adjusted by a frictional braking device22 which includes, for example, a spring leaf 24 in resilient contactwith a roughened circular track 26 provided by pits 27 upon thestationary portion 28 of turntable 16. However, the inherent frictionalresistance of turntable 16 itself might be used to control the degree ofangular rotation of gun 12 caused by each explosion. This amount ofangular motion is advantageously varied in increments which do notrepeat themselves upon successive revolutions to cause the direction offiring to progress about the axis 18 which causes the direction andpattern of explosion to continuously change.

Details of this invention are described in FIGS. 1-4 in whichexplosion-generating means 12 is, for example, a carbide gun whichincorporates automatic means for periodically firing it over aconsiderable period of time. A gun of this type is described in apublication entitled ZON Automatic Scarecrow Model M60 OperatingInstructions; Maintenance Instructions; Parts List published by B. M.Lawrence & Company, 244 California Street, San Francisco 11, California.

Car-bide guns of this type, for example, include a megaphone portion 36which incorporates a combustion chamber 32 and a discharge tube 34.Combustion chamber 32 is charged with acetylene gas from an automatictiming valve section 36 which is supplied with acetylene gas from a gasgenerator 38. FIGS. l4 indicate how this existing carbide gun is mountedupon turntable 16 and its outlet portion somewhat modified in accordancewith this invention. Heretofore, guns 12 incorporating valve 36,generator 38 and their supporting frame work 40 were transported byhandle 42. However, the addi tional weight of turntable 16 and its legs44 make the t41nit now too heavy for one person to carry by handle FIG.2 shows nut and bolt assembly 46 and bearing 48 which form axis ofrotation 18 about which gun 12 rotates. Roller bearings 50 are supportedfrom brackets 52 attached to movable turntable section 14 and rollPatented Oct. 2, 1962 between sections 14 and 16 to promote its rotationin contrast to the frictional resistance of leaf spring 24 which bearsin frictional contact with stationary turntable section 16 to controlthe degree of rotation of turntable portion 14 and gun 12.

Although details of gun 12 are not directly part of this invention, theyare now described to provide a complete description of one embodiment ofthis invention. Gas generator 38 includes a water tank 54 mounted abovea carbide holder 56 which contains a charge of calcium carbide 58. Waterdrops 60 drip upon calcium carbide particles 58 to generate acetylenegas in a wellknown manner, which gas is conducted to timing valve 36through hose 62. FIGS. 3 and 4 show the two extreme conditions ofoperation of timing valve section 36 which includes adiaphragm-actuating linkage 64, a gas-admitting valve 66, and aspark-striking device 68.

Operating stem of gas-admitting valve 66 is actuated to its open orfully raised position shown in FIG. 4 from its closed or loweredposition shown in FIG. 3 by an operating fork 72 pivoted at 74 uponguide frame 76 of valve 66. Fork 72 straddles oscillating lever '78which is pivoted at 80 upon frame 82 of timing assembly 36 as shown inFIG. 2. A spring 84 pulls downwardly upon the end of lever 78 causingits stem 86 lying within fork 72 to be urged upwardly. Stem 86 also liesbetween upper prong 88 and lower prong 90 of diaphragm-actuating plunger92 connected to disc 94 which bears against diaphragm 96 sealing theupper portion of gas cylinder 98 by the retention of its edge undersealing ring 106. Plunger 92 is moved upwardly from the lower positionof FIG. 3 to the upper position in FIG. 4 against the force ofcompression spring 102 by the pressure of gas conducted through hose 62into cylinder 98. In the lower diaphragm position shown in FIG. 3, valve66 is closed which allows the pressure to build up in cylinder 98 toraise diaphragm 96 and plunger 92. Prong 90 attached to plunger 92accordingly raises the contacted stem 86 of lever 78. Stem 86 inresponse contacts the upper arm 164 of fork 72 thereby opening valve 66.

Prior to the opening of valve 66, auxiliary rod 105 attached to the topof diaphragm disc 94 by its loose insertion within cup 103 is alsoraised to the position shown in FIG. 4 by upward movement of diaphragm96 and disc 94 thereby rotating firing-actuating shaft clockwise asshown in FIG. 4 through its rotatable connection to forked connectingrod 112 only partially shown in FIGS. 3 and 4. This rotates locking lug114 also secured to shaft 110' also in a clockwise direction whichallows it to be engaged and latched by stepped locking lug 116 which isconnected to an unlocking arm 118. Both lug 116 and arm 118 arerotatably mounted about pivot 120. A resilient means which is, forexample, a torsion spring 122, schematically indicated in FIGS. 3 and 4,maintains arm 118 and attached latching lug 116 urged in the clockwiselocking direction. In this position it engages lug 114 to maintain shaft110 locked in the clockwise direction in opposition to the force ofanother torsion spring 124.

A spark-actuating lever 126 is secured to the rear end of shaft 110. InFIG. 4 lever 126 is shown in the upper latched position in which itmaintains attached slim connecting rod 128 raised to cock flint-strikingmechanism 130. Flint-striking mechanism 130 is of the pawl and ratchetactuated type which causes wheel 132 to strike a spark from flint 134adjacent aperture 136 in explosive chamber 32 upon each downwardmovement of slim connecting rod 128. A flint magazine 138 extendsdownwardly from the position of flint 134.

Firing Operation The firing operation of gun 12 is described in thefollowing with reference to the extreme conditions of operation shown inFIGS. 3 and 4. FIG. 3 shows the condition of gun 12 immediately after ithas been fired. Diaphragm 96 and disc 94 are urged into the downwardposition by spring 102 because there is no gas in cylinder 98 to opposethe force of spring 102. As gas is generated by the dripping water ingenerator 38 it flows through hose 62 into cylinder 98 which raisesdiaphragm 96 from the condition shown in FIG. 3 to that of FIG. 4. Thispressure can be created because valve 66 is closed in all positions offork 72 connected to valve stem 70 through pin 73 approximately up tothat shown in FIG. 4.

As diaphragm 96 moves upwardly, it carries disc 94 up with it whichraises plunger 92 and rod 106. Lower lug 90 upon plunger 92 raises stem86 upwardly which raises arm 104 of fork 72 along with it. As stem 86rises, it allows unlocking arm 118 to be rotated up in a clockwisedirection by torsion spring 122. This engages latching lug 116 to holdlug 114 connected to shaft 110 in the latched position to which it israised by rod 106 against the force of torsion spring 124. This cocksand latches the flint-striking mechanism 130.

In FIG. 4, lever 86 has raised fork 72 high enough to open valve 66which allows gas to flow through tube 140 from cylinder 98 to valve 66and through tube 142 into explosive chamber 32 in the direction of thearrows disposed alongside tubes 140 and 142. This suddenly relieves thepressure in chamber 98 which permits compression spring 192 to suddenlymove disc 94 and diaphragm 96 downwardly from the position of FIG. 4 tothat of FIG. 3. This causes prong 88 of plunger 92 to suddenly forcelever 86 downwardly and drive arm 144 of fork 72 down to insure closureof valve 66. It also trips unlatching bar 118 to disengage latching lug116 from lug 114 and permit torsion spring 124 to rapidly rotateflint-actuating lever 126 in the counter-clockwise direction. This pullsslim rod 128 rapidly down to cause a spark to be generated byflint-striking mechanism 130. This spark ignites the gas supplied toexplosive chamber 32 which detonates to create a loud noise and a flowof expanding gases flowing outwardly through discharge tube 34. Thiscycle successively repeats as long as the supply of water and carbidelasts.

Another aspect of this invention is the provision of deflecting andchoking means upon the end of discharge tube 34. Deflecting and chokingmeans 150 is, for example, an elbow having an outlet section 152 ofreduced diameter. Outlet section 152 is, for example, formed as asection of a cone which smoothly concentrates the flow of expandinggases 20 through it to increase their velocity. This promotes thereaction of gases 20 upon gun 12 which helps rotate movable turntableportion 14, and it also lengthens the range of the transmission of thesound from each explosion. Outlet section 152 is advantageously disposedwith its longitudinal axis tangentially disposed relative to axis of r0-tation 18 of turntable 16, and the force of the reaction is alsopromoted by disposing the axis of discharge tube 34 itself tangential toaxis of rotation 18.

Rotational O erati n As each explosion is caused with its flow ofexpanding gases 20 discharged from discharge tube 34, it reacts upon thegun and any flow-deflecting or choking means such as elbow 150 to propelmovable turntable portion 14 in a rotational movement. The amount ofthis rotational movement is governed by the frictional resistance toturn ing of the parts of the turntable, and it may be adjusted by aresilient means such as braking device 22 incorporating a leaf springresisting element 24 which engages a circular track 26 which is, forexample, made up of a series of pits 27 upon the upper surface ofstationary turntable portion 28. This amount of rotation isadvantageously adjusted to cause a non-integral amount of rotation suchas slightly more than Mi revolution thereby causing the explosions tooccur at progressively moving stations about axis of rotation 18. Gun12. may, for example, be adjusted to fire every 30 seconds whichprovides a complete rotation in firing within two minutes. This is rapidenough to prevent pests such as blackbirds or crows from encroaching tothe rear of the gun and maintains them substantially cleared from anarea having a radius of approximately 400 yards. This is a substantialimprovement over the ability of the prior nonrotational guns of thistype which are only efiective to approximately 200 yards directly infront of them and 100 yards to their rear with intermediate coveragetherebetween. This invention, therefore, more than quadruples thetheoretical elfective area of coverage of guns of this type.Furthermore, the improvement is even greater than this theoreticalcomparison of areas of coverage because the changing sound caused by thechanges in direction of the gun relative to any given position withinits area of coverage results in uneven variation in the character ofthis sound which prevents any pests such as birds and animals frombecoming accustomed to the sound pattern and encroaching to a minimumtolerable distance. In contrast the changing nature of the soundprovided by this invention prevents the creation of a regular soundpattern to which birds and animals could become accustomed.

What is claimed is:

1. An explosive pest-scaring device comprising an automaticexplosion-generating means which periodically discharges expanding gaseswith a loud sound, a turntable, said explosion-generating means beingmounted upon said turntable, a discharge tube upon saidexplosion-generating means, a flow diverting means mounted upon the endof said discharge tube for directing said discharged expanding gases ata substantial angle to the direction of said discharge tube andsubstantially tangentially relative to the axis of rotation of saidturntable whereby a substantial rotational force is imparted to saidturntable, and the resistance of said turntable to rotation beingadjusted to cause the angle of orientation of said explosion-generatingmeans about the axis of rotation of said turntable to vary after eachexplosion whereby said pests are prevented from encroaching to the rearof said explosion-generating means and varies the sound pattern toprevent said pests from becoming accustomed to it.

2. An explosive pest-scaring device as set forth in claim 1 wherein theextreme end of said discharge tube is reduced in diameter to form achoke which increases the velocity of said discharged expanding gasesand promotes the transmission of the sound of said explosions to longerdistances.

3. An explosive pest-scaring device as set forth in claim 1 wherein saidflow diverting means comprises an elbow mounted upon the end of saiddischarge tube.

4. An explosive pest-scaring device as set forth in claim 3 wherein anoutlet choke is mounted upon the end of said elbow for increasing therotational force caused by said explosion-generating means and thedistance to which said sound is transmitted.

5. An explosive pest-scaring device as set forth in claim 4 wherein theaxis of said outlet choke is disposed approximately tangentially to theaxis of rotation of said turntable.

6. An explosive pest-scaring device as set forth in claim 5 wherein saiddischarge tube is mounted remote from the axis of rotation of saidturntable and substantially tangentially relative thereto.

References Cited in the file of this patent UNITED STATES PATENTS2,138,282 Lanninger Nov. 29, 1938 2,719,751 Orr Oct. 4, 1955 FOREIGNPATENTS 633,933 France Feb. 6, 1928 200,445 Australia Dec. 1, 1955209,727 Australia Feb. 23, 1956

